Ford 2006 F-250 Owner's Manual page 187

Using the N (Neutral) position
The transfer case neutral position overrides the transmission and
puts the vehicle in neutral regardless of transmission gearshift
lever position. The vehicle can move forward or backwards.
This position should only be used
when towing the vehicle.
Do not leave the vehicle unattended with the transfer case in the
N (Neutral) position. Always set the parking brake fully and turn
off the ignition when leaving the vehicle.
Using the Electronic Shift On the Fly (ESOF) 4WD system
(if equipped)
Positions of the electronic shift system
The electronic shift 4WD system is designed to allow up to 45
seconds before a shift command is performed. In the event that
conflicting shift commands are selected, allow up to 45 seconds
for the shift command to be performed prior to reporting any
shift concerns to your authorized dealer.
Note: Some noise may be heard as the 4WD system shifts or engages.
This is normal.
2H (2WD High) – For general on-road driving. Sends power to the rear
wheels only.
4H (4WD High) – For winter and off-road conditions. Sends power to
front and rear wheels.
4L (4WD Low) – For low-speed off-road applications that require extra
power such as steep grades, deep sand or pulling a boat out of the water.
Sends power to front and rear wheels.
2006 F-250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA (fus)
Driving
2H
4H
N
4L
187